A prospective cohort study to investigate parental stress and child health in low-income Chinese families: protocol paper.

introductionChronic stress has adverse effects on health. Adults and children from low-income families are subject to multiple sources of stress. Existing literature about economic hardship mostly focuses on either adults or children but not both. Moreover, there is limited knowledge on the relationship between parental generalised stress and child health problems. This study aims to explore the bidirectional relationship between parental stress and child health in Chinese low-income families and to identify other modifiable factors influencing this relationship. METHODS AND ANALYSIS: This prospective cohort study will sample 254 low-income parent-child pairs and follow them up for 24 months with assessments at three time points (baseline, 12 and 24 months) on parental stress, health-related quality of life (HRQOL) and child health and behaviour using both subjective measures and objective physiological parameters. This study will collect data using standardised measures on HRQOL and behaviours of children as well as on HRQOL, mental health and stress levels of parents along with physiological tests of allostatic load and telomere length. The mediating or moderating effect of family harmony, parenting style and neighbourhood conditions will also be assessed. Data will be analysed using latent growth modelling and cross-lagged path analysis modelling to examine the bidirectional effect of parental stress and child health over time. Mediation and moderation analysis will also be conducted to examine the mechanism by which the variables relate. ETHICS AND DISSEMINATION: This study was approved by the institutional review board of the University of Hong Kong-the Hospital Authority Hong Kong West Cluster, reference no: UW 16-415. The study findings will be disseminated through peer-reviewed publications and international conferences. TRIAL REGISTRATION NUMBER: NCT03185273; Pre-results.